ZCZC MIATCDEP5 ALL TTAA00 KNHC DDHHMM TROPICAL STORM DALILA DISCUSSION NUMBER 4 NATIONAL WEATHER SERVICE MIAMI FL 2 PM PDT SAT JUL 21 2001 THE INITIAL MOTION ESTIMATE IS 300/11. THE AVIATION MODEL MAINTAINS A RIDGE TO THE NORTH OF THE STORM SO THAT THE INTIAL MOTION SHOULD CONTINUE. THIS IS SUPPORTED BY MOST OF THE TRACK GUIDANCE MODELS. THE TRACK FORECAST IS SIMILAR TO THE PREVIOUS ADVISORY EXCEPT ADJUSTED SLIGHTLY TO THE RIGHT. DVORAK INTENSITY ESTIMATES HAVE INCREASED TO 45 KNOTS AND SO HAS THE OFFICIAL WIND SPEED. THE OFFICIAL FORECAST BRINGS THE WIND UP TO 85 KNOTS BY 48 HOURS FOLLOWING THE SHIPS MODEL. THE GFDL MODEL IS EVEN MORE AGGRESSIVE. THE FORECAST TRACK AND WIND SPEED RADII BRING 35 KNOT WINDS ALMOST TO THE COAST OF MEXICO AND THE TROPICAL STORM WATCH MAY HAVE TO BE CHANGED TO A TROPICAL STORM OR EVEN HURRICANE WARNING LATER TONIGHT OR EARLY SUNDAY...DEPENDING ON THE EXACT TRACK OF DALILA. FORECASTER LAWRENCE FORECAST POSITIONS AND MAX WINDS INITIAL 21/2100Z 13.5N 97.5W 45 KTS 12HR VT 22/0600Z 14.2N 98.8W 55 KTS 24HR VT 22/1800Z 15.1N 100.6W 65 KTS 36HR VT 23/0600Z 15.7N 102.1W 75 KTS 48HR VT 23/1800Z 16.2N 103.6W 85 KTS 72HR VT 24/1800Z 17.0N 106.0W 85 KTS NNNN